Additional file 4: of A repeat region from the Brassica juncea HMA4 gene BjHMA4R is specifically involved in Cd2+ binding in the cytosol under low heavy metal concentrations

Data S4. Ni, Co and Pb contents of yeast and E. coli expressing BjHMA4R. a, b, d, e, g, h: Yeast BY4741 and YK44 cells transformed with a pYES2 plasmid or a pYES2 plasmid that harbored BjHMA4R were grown in normal liquid YPD medium overnight. Then, they were supplemented with 200 μM Ni(NO3)2, Co(NO3)2 and Pb(NO3)2. The cells were incubated at 30 °C for 30 min, 70 min, 5 h, 10 h or 21 h. c, f, i: E. coli BL21 cells transformed with a pEASY-Blunt E1 expression plasmid or a pEASY-Blunt E1 expression plasmid that harbored BjHMA4R were grown in normal liquid LB medium overnight, then supplemented with 200 μM Ni(NO3)2, Co(NO3)2 and Pb(NO3)2. The cells were incubated at 37 °C for 10 h and 21 h. The metal contents of the samples were analyzed with inductively coupled plasma-mass spectrometry (ICP-MS). The results are the means ± SEs of four independent experiments performed with four different colonies. Different letters above the columns indicate significant differences (P < 0.05) between cell groups under the same stress treatment. (JPG 637 kb